a solution eluded past presidents including george w. bush. >> lal immigration is one of the top concerns of the american people. congress' fail ture to act is a disappointment. >> reporter: obama did announce hess administration would stop deporting some young undocumented immigrant but was taken to task at a town hall for not doing something bigger. >> you promised that. a promise is a promise. with all due respect -- >> what i promised was that i would work every single day as hard as i can to make sure that everybody in this country, regardless of who they are, what they look like, where they come from they'd have a fair shot at american dream. >> reporter: still, hispanic americans, the fastest growing voter bloc, helped propel obama to a second term. a wake-up call for republicans. >> i do know there are a lot of democrats in congress who once and for all want to solve this problem, fix this mess, a broken immigration system, and many of always degree with that. >> want to bring in brianna keilar from the white house. first of all,